The antidote of paracetamol poisoning
High-Yield Explanation
Overdosage of PCM is treated with N-acetyl cysteine used orally within 16 hours after ingestion at a loading dose of 140 mg/ Kg diluted to 5% solution orally.
Followed by 70 mg /Kg q 4hr for another 2 days PCM is the most common analgesic, antipyretic used in children Paracetamol produces a highly reactive toxic minor metabolites -
N-acetyl benzoquinone amine. Normally this metabolite is detoxified by conjugation with glutathione - when a very large dose of paracetamol is taken glucuronidation capacity is saturated and this metabolite is not detoxified (Hepatic glutathione is depleted) ↓
Excess metabolite N acetyl benzoquinone** binds to the protein in liver cells (and renal tubules) ↓ Centrilobular hepatic necrosis** This single most important laboratory test in a patient who present after acetaminophen is the acetaminophen level in the serum.